I need to do a homework and write a bit about ethernet. I am totally new to the topic, so i thought maybe some one could give me a hand by explaining me a bit about what scalability is, when talking about ethernet networks?

I have experience with web programming, and when we talk about scalability, we think in the performance of the application when the number of users or requests increase(Work load increases).
I suppose this has to be something similar in networks.
So what is for you scalability of an ethernet network?

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All those mean differen thigns and different ethernet level technologies migitate some of them more or less (switchesvs. hubs for one and two for example).

I would assume the most likely answer is network speed, which would be indicated by the different ethernet speeds (10megbit, 100megabit, 1 gigabit and 10gigabit).

Then we have whole network scalability. For example a switch with 48 ports - how scalable is it? These days mostly a non issue (answer: 96gigabit, the switch can hadnle the maximum theoretical traffic), but in the past a lower priced switch may not have enough processing power to handle this under all circumstances. As Ethernet is not necessarily an internet technology, requirements for speed and latency are stricter. For example I am using ethernet (like most people) between application servers and database servers, and there I push a LOT more bandwidth than most web servers do ;)

Just imagine, ive got all servers configured to 192.168.XXX.0/24 subnets. Yours project goes ok. You've got subnetworks for office-managers/employes/printers and so on. And now when you reached 192.168.255.0/24 network you have to add some subnet for yours city-X parntners. what would you do now? (no more subnets, and you should change all of this to 172.16.0.0 or 10.0.0.0 subnets or use vlans)

Or you ve got all yours routers and switches that doesnt support vlans, and you shoud work with em.